Fluorine is more electronegative than either boron or phosphorus. What conclusion can be drawn from the fact that ${\mathrm{BF}}_3$ has no dipole moment but ${\mathrm{PF}}_3$ has?

1.  ${\mathrm{BF}}_3$ is spherically symmetrical, ${\mathrm{PF}}_3$ is not

2.  ${\mathrm{BF}}_3$ molecule must be linear

3.  The atomic radius of P is larger than the atomic radius of B

4.  The ${\mathrm{BF}}_3$ molecule must be planar triangular

Borazine is obtained by reaction of:

1.  ${\mathrm{NH}}_3+{\mathrm{B}}_2{\mathrm{H}}_6 \mathrm{in} 2 : 1 \mathrm{ratio}$

2.  ${\mathrm{NH}}_3+{\mathrm{B}}_2{\mathrm{H}}_6 \mathrm{in} 1 : 2 \mathrm{ratio}$

3.  ${\mathrm{NH}}_3+{\mathrm{B}}_2{\mathrm{H}}_6 \mathrm{in} 1 : 4 \mathrm{ratio}$

4.  ${\mathrm{NH}}_3+{\mathrm{B}}_2{\mathrm{H}}_6 \mathrm{in} 4 : 1 \mathrm{ratio}$

An incorrect statement among the following regarding Al₂Cl₆ is:

Carbon dioxide is a gas but silica is a solid because:

1.  carbon dioxide is composed of discrete covalent ${\mathrm{CO}}_2$ molecules whereas silica has continuous

     tetrahedral structure

2.  ${\mathrm{CO}}_2$ molecules are lighter than ${\mathrm{SiO}}_2$ molecules

3.  ${\mathrm{CO}}_2$ is more acidic than ${\mathrm{SiO}}_2$

4.  melting point of silica is very high

Which of the following shows bond in silicone?

1.  $\mathrm{Si}—\mathrm{C}—\mathrm{Si}—\mathrm{O}—\mathrm{Si}$

2.  $\mathrm{Si}—\mathrm{C}—\mathrm{Si}—\mathrm{C}—\mathrm{Si}$

3.  $—\stackrel{\mathbf{|}}{\mathrm{Si}}—\mathrm{O}—\stackrel{\mathbf{|}}{\mathrm{Si}}—\mathrm{O}—\stackrel{\mathbf{|}}{\mathrm{Si}}—$

4.  $\mathrm{Si}—\mathrm{Si}—\mathrm{Si}—\mathrm{Si}$

Mica is chemically:

1.  potassium alumino silicate having sheet structure

2.  calcium alumino silicate having fibrous structure

3.  calcium magnesium silicate having three dimensional network

4.  hydrated sodium alumino silicate having three dimensional network

The incorrect statement among the following is -

1. $\mathrm{Ge}{\left(\mathrm{OH}\right)}_2$ is amphoteric

2. ${\mathrm{GeCl}}_2$ is more stable than ${\mathrm{GeCl}}_4$

3. ${\mathrm{GeO}}_2$ is weakly acidic

4. GeCl₄ + 2HCl ⇄ H₂[GeCl₆]

Silicon carbide is used as:

${\mathrm{Mg}}_2{\mathrm{C}}_3$ has the following characteristics:

1.  It is called magnesium allylide

2.  It contains ${\mathrm{Mg}}^{2+}$ and ${\mathrm{C}}_3^{4-}$ions

3.  It on hydrolysis gives propyne

4.  All of the above

$\mathrm{CO}$ reacts with chlorine in presence of sunlight to give:

1.  ${\mathrm{COCl}}_2$

2.  ${\mathrm{CO}}_2$

3.  ${\mathrm{CCl}}_4$

4.  ${\mathrm{CHCl}}_3$